Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(\-((0[0-9]|1[0-2]):00|0[39]:30)|\+((0[0-9]|1[0-4]):00|(0[34569]|10):30|(0[58]|12):45))`) var str = `-99:99 -13:00 -12:45 -12:30 -12:15 -09:15 +02:15 +03:44 +03:45 +03:46 +14:15 +14:45 +99:99 -12:00 -11:00 -10:00 -09:30 -09:00 -08:00 -07:00 -06:00 -05:00 -04:00 -03:30 -03:00 -02:00 -01:00 -00:00 +00:00 +01:00 +02:00 +03:00 +03:30 +04:00 +04:30 +05:00 +05:30 +05:45 +06:00 +06:30 +07:00 +08:00 +08:45 +09:00 +09:30 +10:00 +10:30 +11:00 +12:00 +12:45 +13:00 +14:00 ` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/